Iterates over the block according to how this Enumerator
was constructed. If no block and no arguments are given, returns self.
"Hello, world!".scan(/\w+/) #=> ["Hello", "world"] "Hello, world!".to_enum(:scan, /\w+/).to_a #=> ["Hello", "world"] "Hello, world!".to_enum(:scan).each(/\w+/).to_a #=> ["Hello", "world"] obj = Object.new def obj.each_arg(a, b=:b, *rest) yield a yield b yield rest :method_returned end enum = obj.to_enum :each_arg, :a, :x enum.each.to_a #=> [:a, :x, []] enum.each.equal?(enum) #=> true enum.each { |elm| elm } #=> :method_returned enum.each(:y, :z).to_a #=> [:a, :x, [:y, :z]] enum.each(:y, :z).equal?(enum) #=> false enum.each(:y, :z) { |elm| elm } #=> :method_returned
Returns a hash of parsed elements.
Creates a new Date
object by parsing from a string according to some typical XML
Schema formats.
Date.xmlschema('2001-02-03') #=> #<Date: 2001-02-03 ...>
This method is equivalent to strftime(‘%F’).
Creates a new DateTime
object by parsing from a string according to some typical XML
Schema formats.
DateTime.xmlschema('2001-02-03T04:05:06+07:00') #=> #<DateTime: 2001-02-03T04:05:06+07:00 ...>
This method is equivalent to strftime(‘%FT%T%:z’). The optional argument n
is the number of digits for fractional seconds.
DateTime.parse('2001-02-03T04:05:06.123456789+07:00').iso8601(9) #=> "2001-02-03T04:05:06.123456789+07:00"
Parses date
as a dateTime defined by the XML
Schema and converts it to a Time
object. The format is a restricted version of the format defined by ISO 8601.
ArgumentError
is raised if date
is not compliant with the format or if the Time
class cannot represent specified date.
See xmlschema
for more information on this format.
You must require ‘time’ to use this method.
Returns a string which represents the time as a dateTime defined by XML
Schema:
CCYY-MM-DDThh:mm:ssTZD CCYY-MM-DDThh:mm:ss.sssTZD
where TZD is Z or [+-]hh:mm.
If self is a UTC time, Z is used as TZD. [+-]hh:mm is used otherwise.
fractional_digits
specifies a number of digits to use for fractional seconds. Its default value is 0.
You must require ‘time’ to use this method.
Return a value from the database by locating the key string provided. If the key is not found, returns ifnone
. If ifnone
is not given, raises IndexError
.
Calls the block once for each [key, value] pair in the database. Returns self.
Yields the value of each struct member in order. If no block is given an enumerator is returned.
Customer = Struct.new(:name, :address, :zip) joe = Customer.new("Joe Smith", "123 Maple, Anytown NC", 12345) joe.each {|x| puts(x) }
Produces:
Joe Smith 123 Maple, Anytown NC 12345
Reads and returns a character in raw mode.
You must require ‘io/console’ to use this method.
Enables/disables echo back. On some platforms, all combinations of this flags and raw/cooked mode may not be valid.
You must require ‘io/console’ to use this method.
Yields self
with disabling echo back.
STDIN.noecho(&:gets)
will read and return a line without echo back.
You must require ‘io/console’ to use this method.
Opens the given path, returning the underlying file descriptor as a Integer
.
IO.sysopen("testfile") #=> 3
Executes the block for every line in the named I/O port, where lines are separated by sep.
If no block is given, an enumerator is returned instead.
IO.foreach("testfile") {|x| print "GOT ", x }
produces:
GOT This is line one GOT This is line two GOT This is line three GOT And so on...
If the last argument is a hash, it’s the keyword argument to open. See IO.read
for detail.
Executes the block for every line in ios, where lines are separated by sep. ios must be opened for reading or an IOError
will be raised.
If no block is given, an enumerator is returned instead.
f = File.new("testfile") f.each {|line| puts "#{f.lineno}: #{line}" }
produces:
1: This is line one 2: This is line two 3: This is line three 4: And so on...
Writes the given string to ios using a low-level write. Returns the number of bytes written. Do not mix with other methods that write to ios or you may get unpredictable results. Raises SystemCallError
on error.
f = File.new("out", "w") f.syswrite("ABCDEF") #=> 6
Reads maxlen bytes from ios using a low-level read and returns them as a string. Do not mix with other methods that read from ios or you may get unpredictable results.
If the optional outbuf argument is present, it must reference a String, which will receive the data. The outbuf will contain only the received data after the method call even if it is not empty at the beginning.
Raises SystemCallError
on error and EOFError
at end of file.
f = File.new("testfile") f.sysread(16) #=> "This is line one"
Immediately writes all buffered data in ios to disk. Note that fsync
differs from using IO#sync=
. The latter ensures that data is flushed from Ruby’s buffers, but does not guarantee that the underlying operating system actually writes it to disk.
NotImplementedError
is raised if the underlying operating system does not support fsync(2).
Immediately writes all buffered data in ios to disk.
If the underlying operating system does not support fdatasync(2), IO#fsync
is called instead (which might raise a NotImplementedError
).
Returns the current “sync mode” of ios. When sync mode is true, all output is immediately flushed to the underlying operating system and is not buffered by Ruby internally. See also IO#fsync
.
f = File.new("testfile") f.sync #=> false
Sets the “sync mode” to true
or false
. When sync mode is true, all output is immediately flushed to the underlying operating system and is not buffered internally. Returns the new state. See also IO#fsync
.
f = File.new("testfile") f.sync = true